Retrospective Chart Review of Children With Type 2 Diabetes Mellitus Evaluating the Efficacy of Metformin vs. Insulin vs. Combination Insulin/Metformin

Objectives: Type 2 diabetes mellitus is a growing problem in pediatrics and there is no consensus on the best treatment. We conducted this chart review on newly diagnosed pediatric patients with type 2 diabetes mellitus to compare the effect of treatment regimen on body mass index (BMI) and hemoglobin A(1c) over a 6-month period. Methods: We conducted a retrospective chart review on patients with type 2 DM who presented to Nationwide Children's Hospital. Data were collected on therapy type, BMI, and hemoglobin A(1c) over a 6-month follow-up. Therapy type was divided into metformin, insulin, or combination insulin and metformin. A total of 1997 charts were reviewed for inclusion based on ICD-9 codes consistent with a diagnosis of diabetes, abnormal oral glucose tolerance test, or insulin resistance. Results: Of the 47 charts eligible for the review, 26 subjects were treated with metformin 1000-1500 mg daily, 14 patients were treated with insulin therapy, and 7 patients were treated with a combination of insulin and metformin therapy. At baseline, the only significant difference among groups was A(1c) (P = 0.012). In regression analysis with baseline A(1c) as a covariate, the only predictor of change in A(1c) over time was the A(1c) at onset (P < 0.001). Therapy type was not predictive of change (P = 0.905). Regression analysis showed a greater BMI at onset predicted a greater decrease in BMI (P = 0.006), but therapy type did not predict a change (P = 0.517). Conclusion: Metformin may be as effective as insulin or combination therapy for treatment of diabetes from onset to 6-month follow-up.